This should always return identity unless flag use_parent_model_frame is true in sdf 1.5 or using sdf 1.4-, i.e. bug described in issue #494 is present. In addition, if use_parent_model_frame is true, and the parent link of the joint is world, the axis is defined in the world frame. The value of axisParentModelFrame is used to determine the appropriate frame internally.

Parameters

[in]

_index

joint axis index.

Returns

Orientation of axis frame relative to joint frame. If supplied _index is out of range, or use_parent_model_frame is not true, this function returns identity rotation quaternion.

This should always return identity unless flag use_parent_model_frame is true in sdf 1.5 or using sdf 1.4-, i.e. bug described in issue #494 is present. In addition, if use_parent_model_frame is true, and the parent link of the joint is world, the axis is defined in the world frame. The value of axisParentModelFrame is used to determine the appropriate frame internally.

Parameters

[in]

_index

joint axis index.

Returns

Orientation of axis frame relative to joint frame. If supplied _index is out of range, or use_parent_model_frame is not true, this function returns identity rotation quaternion.

The ratio is given in the form of MOI_child / MOI_parent. If MOI_parent is zero, this funciton will return 0. The inertia ratio for each joint axis indicates the sensitivity of the joint to actuation torques.

Computes moment of inertia (MOI) across an arbitrary axis specified in the world frame.

The ratio is given in the form of MOI_child / MOI_parent. If MOI_parent is zero, this funciton will return 0. The moment of inertia ratio along constrained directions of a joint has an impact on the performance of Projected Gauss Seidel (PGS) iterative LCP methods.

Computes moment of inertia (MOI) across an arbitrary axis specified in the world frame.

The ratio is given in the form of MOI_chidl / MOI_parent. If MOI_parent is zero, this funciton will return 0. The moment of inertia ratio along constrained directions of a joint has an impact on the performance of Projected Gauss Seidel (PGS) iterative LCP methods.

Note that the unit of force should be consistent with the rest of the simulation scales. Force is additive (multiple calls to SetForce to the same joint in the same time step will accumulate forces on that Joint). Forces are truncated by effortLimit before applied.

Note that the unit of force should be consistent with the rest of the simulation scales. Force is additive (multiple calls to SetForceImpl to the same joint in the same time step will accumulate forces on that Joint).

In ODE and Bullet, the SetVelocityMaximal function is used to set the velocity of the child link relative to the parent. In Simbody and DART, this function updates the velocity state, which has a recursive effect on the rest of the chain.

The URI includes the world where the entity is contained and all the hierarchy of sub-entities that can compose this entity. E.g.: A link entity contains the name of the link and the model where the link is contained.

Member Data Documentation

This is the xyz offset of the joint frame from child frame specified in the parent link frame

ignition::math::Pose3d anchorPose

protectedinherited

Anchor pose specified in SDF <joint><pose> tag.

AnchorPose is the transform from child link frame to joint frame specified in the child link frame. AnchorPos is more relevant in normal usage, but sometimes, we do need this (e.g. GetForceTorque and joint visualization).